Loud-speaking receiver



Dec. 15,1925

W. J. BEACH' LOUD SPEAKING RECEIVER Filed March 30 1925 6 Sheets-Sheet 1 INVENTE] Fl:

ATTX

' Dec; 15 1925.

W. J. BEACH LOUD SPEAKING RECEIVER Filed March so, 1925 a sheets-sheet 2 Dec. 15,1925. Y v 1,566,065

w. J. BEACH Y LOUD SPEAKING RECEIVER Filed March 30,1925 6 sheets-sheet s Dec. 15, 925. 1,566,065

w. J. BEACH LOUD SPEAKING RECEIVER Filed March 30 1 925 6 Sheets-Sheet 4 IN ENTURQ W. J. BEACH LOUD SPEAKING RECEIVER Filed March 30, 1925 6 Sheets-Sheet 5 lNVE NTEI R:

Dec. 15,1925. 1,566,065

W. J. BEAQH LOUD'SPEAKING RECEIVER Filed March 30, 1925 6 Sheets-Sheet 6 v lNvENT 38 UR I Patented Dec. 15, 1925.

UNITED STATES PATENT OFFICE.

WILLIAM J. BEACH, OF TORONTO, ONTARIO, CANADA.

LOUD-SPEAKING nncnrvnn.

Application filed March 30, 1925. Serial No. 19,299.

' My invention relates to loud speaking re- 1 ceivers and pertains to the electro-magnetic type of such receivers which perhaps find their chief use in connection-with radio re.-

- ception.

The principal objects contemplated by my invention comprise producing a loud speaker which is extremely efficient in sound reproduction, both from the standpoint of volume and'clarity of reproduction; to provide a micrometer adjustment between the electro-magnetic elements to ensure high quality of reproduction; to provide a device in which the various parts are freely accessible; to provide a sound chamher which may be acoustically tuned and 1n which the means for reproducing the sound are contained in the chamber; and further to provide a device, the diaphragm of which is such that equal tonal .value is given to the reproduction of sound therefrom by each of the diaphragm surfaces.

I accomplish all these very desirable features andothers, which will hereinafter be discussed, by means of the novel device described in the specification and illustrated in the drawings which accompany and form a part of this specification.

In the drawings, in which like numerals designate corresponding parts throughout Fig. 1 is a side elevation of my complete device. a

Fig. 2 is a broken elevation of the with the outer cover and flare removed.

Fig. 3 is a front view taken on the line 33 of Fig. 2.

Fig. 4 is a broken sectional view of a portion of the device taken on the line 4-4 of Fig. 3. p

Fig. 5 is a front view of aportion' of the device taken on the line 55 of Fig. 2.

Fig. 6 is a sectional view of the sound deflecting member, taken -on the line 66 of Fig. 5. r

Fig. 7 is a front view taken on' the line 7-7 of Fig. 2.

same

Fig. 8 is a broken sectional view of the diaphragm of'the devicetaken on the line 8.8 of Fig. 7;

F ig. 9 is a magnet. I

Fig. 10 is a fragmentary view of the permanent magnet with the extension pole and .pole pieces in position.

detail view of the permanent Fig. 11 is a modification of the electro magnetic system of Figs. 9 and 10.

pieces.

Referring now to Figs. 1 and 2 particularly, my device comprises a containing and supporting casing or housing 1, which is preferably cast of aluminum in the form of three co-axial right cylinders of variant diameter. The largest of these cylinders supports a hell .or flare 2 which is the acoustic outlet of the speaker. The device as a whole is' adapted to be sup orted by a base 4: which supports a rotata le stud 54 provided with a knurled adjustment wheel '5 by which the device may be rotated in a horizontal plane. The stud 54; further supports a bracket 3 in which'the device is journalled as shown to permit the device to be rotated in a vertical plane. The knurled knobs as 6 are provided to clamp the device at any desired-vertical angle. A removable plate 12 is provided whereby the interior mechanism of the device may be viewed for adjustment purposes, as will hereinafter be explained.

Referring now particularly to Fig. 2 in which the casing 1 is represented in dotted outline and the flare or bell 2 is omitted, my device comprises a mechanism supporting member 14 adapted to slide within the .middle portion ofthe outer casing l as shown. The member 14 is cast of aluminum in the form of a hollow cylinder provided with a flange 94 and a collarlS of lar er diameter than the body of the member. he rear portion of the member is closed by a plate 55 secured to the member by screws as shown. The plate 55 carries a central boss 56. A push rod 15 which is threaded into the outer.casing 1 and provided with a knurled knob 9 is. further provided with a plate 57 adaptedto make contact with the boss 56 carried by plate 55. brated dial 11 is provided on,the casing 1 and a pointer. 10 is attached to the push rod 15,v thus providing a means for accurately Fig. 12 is a side view of one of the pole A cali- 'the member 14 piovided with apertures therein to freely sl over studs 17. T. T? and 87. which are screwed into the casing 1 as-indicated. Springs 16 and 413 are. pro

vided between the cap'ot each of the studs 1?, 4T. 77 and 81' and the tiange of the member 14 and exert pressure to lieep the member always in contact with the enlarged end of the push or adjusting rod 15.

As shown in Fig. 3. a pern'ianent magnet 19 of substantially circular form is carried within the collar 18 of the member 14 and is held in place. thereby- .)y means of lugs 20 and (30 which are secured to the collar of the member l4 and in which are secured set screws 22 and ('2 to retain the permanent magnet 19. as shown in Figs. 3 and 4., A. guide web 2 is provided and erured to the member .14, as indicated in Fig. 3. Extension pole pieces 24 and (it are secured to thepermanent magnet 19 and extend toward the centre thereof and serve to support pole pieces 42 and (32 and operating magnet coils 23 and (33. connections 2i tori which pass through a slot 26 in the member 14 and are connected to binding posts as 7 and 8, Fig. 1..

As shown in Figs. 3 and 4, the operating magnets are held securely in position by means of screws as 25 and 95, which are threaded into bosses on the member 14. An armature 80 is maintained adjacent to the pole pieces of the operating magnets 23 and (33 and is provided with a rod attached thereto, which passes through a central guide aperture in the guide web 21 and further through an aperture in a sound deflecting member 28, which is shown in Figs. 5 and 6. A

This sound deflecting member. .28 is formed in the shape indicated and is movable longitudinally within themember 1. It is held in place by means of studs as 49 carried in slots 29 and 59 and providedwith spring clips as 13. The central aperture in the sound deflecting member 28 is of such,

diameter as to give full clearance for the 'rod 34. The, extremity of the rod 34 ,as shown in Figs. 7 and 8 is securely clamped as indicated in Fig. 8 to the mid portion of two cone. shaped diaphragms 32 and 33 which are clamped between retaining rings as 36 and 37 and a spacer 30, all of which are provided with a series of annular sound outlets or ports as 38 located near the outer periphery of the diaphragms. The diaphragm organization is held in the casing l by means of screws as 31. The clamping means which secures the rod 34 to the diaphragms further functions as a means for tensioning or stretching the diaphragms.

It will be noted from the foregoing that the knurled knob 9 may be operated to push the member 14 carrying the clectro-magnetic organization against the pressure exerted by the springs 16 and tG to vary the distance between the pole pieces and the armature carriedby the rod 34, which passes through the guide web 21, the sound deflecting member and attached to the cone shaped diaphragms 32 and 33. The distance between the arnratnre and pole pieces may be observed through the port in the casing 1 closed by the plate 12. The guide web 21 acts. as its name implies, to constrain the vibrations of the rod 34 axially and to prevent any lateral motion thereof. It will be noted that the sound deflecting member 28 is held by means of the. three spring clips as 13 and may be moved toward or away from the diaphragms to vary the 1 acoustic period of the sound chamber formed between the sound deflecting member and the diaphragms. It will be turther noted that the apeXes of the two diaphragms the laminations as 41 are introduced. Thelaminations are carried-through the operating coils and serve as the operating pole pieces shown as 42. The laminations are held in the permanent magnet by means of a clamping screw as 22, while the laminations 42 carrying the coil 23 are held in the extension pole laminations 41 by means 01'' screws 25 and which clamp the organization to the member 14,- as shown in Figs. 3 and 4. An alternative method of connecting the extension pole piece laminations is shown in Fig. 11, in which they are shown as composed of two groups 43 and 44 carried on either side of the permanent magnet 39 and in turn carrying the pole piece laminations 42. The operating extremity tit) magnetic organization is so well known in I the art as to need no explanation here, and 1t is deemed sufiicient to explain and discuss the characteristics of the novel features of my device.- The provision of between the extension pole piece and the of the rod and thus prevents lost motion and ensures ample volume. The provision of the double cone shaped diaphragms ensures that each surface of the diaphragm will be similarly utilizedin the production of the sound wave and the air chamber between the diaphragms acts as an acoustic loading for the device to revent distortion. Further, the provision o the sound deflector serves to prevent reflection of sound into the operating mechanism of the deviceand to reflect sound from the surface of the inner diaphragm through the annular ports as 28 which surround the diaphragm mechanism as a whole. The sound deflector 28 may be moved to tune the resonant chamber as desired to improve the quality of reproduction; It will be noticed in my device that the acoustic outlet 2. or bell is at no place throughout its length of smaller diameter than the diameter of the diaphragms,

thus there can result no acoustic choking, which is found to "be .detrimental in other devices of this class.'

From the above it will be noted that I have produced a device which will be effective in the translation of electrical energy into sound waves with the highest cfficiency. That I have further produced a device embodying features tending to increase the tonal quality of such reproduction, by refinementsof. adjustment and by refinements of tuning the acoustic chamber and efliciently directing the sound there-' from. While I have one embodiment of my device, I wish it to be clearly understood that I may vary the details thereof-without departing from the spirit or narrowing the scopeofmy inven tion.

what I claim as new and desire to secure by United States Letters Patent is as fol lows 1. In a loud speakingreceiver, an electro-magnetic system, anarmature operated.

thereby, a. diaphragm operated by said armature, a sound deflector disposed between said electro-magnetic system and said diaphragm, and sound ports near. the outer periphery of said diaphragm to a permit egress of sound reflected from said sound "deflector.

disclosed and described but .said rod.

2. Ina loud speaking receiver, an electro- -magnctic system, an armature operated thereby, a diaphragm operated by said armature, a sound deflector disposed between said electroanagnetic system and said diaphragm, and sound ports at the outer periphery of said diaphragm to permit egress of sound reflected from said sound deflector.

3. In a loud speaking receiver, an electromagnetic system, an armature operated thereby, a diaphragm operated by said armature, a sound deflector disposed between said electro-magnetic system and said diaphragm and adjustable with respect to its distance from said diaphragm, and sound ports near the outer periphery of said diaphragm to permit egress of sound reflected from said sound deflector.

4] In a loud speaking receiver, an electromagnetic system, an armature operated thereby, a diaphragm, a connection between said armature and said diaphragm, a guide for said connection, a sound deflector disposed between said electro-magnetic system and said diaphragm, and an acoustic outlet the minimum diameter-of which is substantially the same as that of said diaphragm.

5.; In aloud speaking receiver, a housing, I

supporting means for said housing, an acoustic outlet mounted on one extremity of said housing, a support adapted to permit said housing to be rotated in two planes, an .electro-magnetic system within said housing, a diaphragm, asound deflector disposed between said .electro-magnetic system and said diaphragm and means whereby said deflector maybe moved relatively to said diaphragm. .6. In a loud speaking receiver, a housing,

a flare mounted on said housing, means for supporting said housing whereby said housing may be moved in two planes, a polarized electro-magnetic system, an armature therefor, a diaphragm comprising two cone shaped members with their apexes in contact, a rod connecting the apexes of said diaphragms to said armature and a guide for 7. In a loud speaking receiver, a housing, a flare mounted on said hous1ng,'means for supporting said housing to permit movevment thereof in two planes, a polarized elec- Havmg thus fully described my invention tro-magnetic system, an armature therefor, a rod, a d1a hragm connected to said arma ture throng said rod, 3. guide forsaid rod and a yisible micrometer means for adjustmg the distance between .sa1d electro-magneti'c "system and said armature.

8. In a loud speaking receiver, a permar ing eiecti-o-niegzlets disgosed on said pole pieces, en armature, micremetei' means for adjusting the distance between said gale pieces and said armature end adiaphzagm adapted to be operated by said armature.

S). In a loud s ceeking receiver, a permanent magnet, extension pole pieces therefor comprising ie'minetions adapted to make contact with said permanent magaet e15 3Q plurality of pesii'uiciis with rescect to the cross section thereof, iamiiiei'led peie pieces carried by said extension sole pieces the lamina-times being of veriai s'iengbhs to present serrated pole feces, operating eieciziomagnets disposed on said pole pieces, an armature, micrometer means for adjusting the distance between said pale pieces said armature and e diaphmgm adapted to be operated by said ermamre.

i J. BEACH. 

